1. Field of the Invention
The present invention relates to novel aspartyl dipeptide amide derivatives that are useful as a low-calorie sweetener for food and beverage products.
2. Discussion of the Background
In recent years, eating habits have improved to a great extent, and weight gain caused by excessive consumption of sugar as well as health problems associated with this weight gain have been at issue. Therefore, the development of a low-calorie sweetener to replace sugar has been a major goal. Aspartame is a widely used sweetener which has excellent safety and sweetness properties. However, aspartame contains an ester linkage and, as a result, is unstable. In order to improve the stability and the sweetness intensity, aspartyl-D-amino acid amide derivatives lacking an ester linkage have been investigated, see, for example, U.S. Pat. Nos. 4,411,925 and 5,286,509. French Patent No. 2,697,844 describes aspartyldipeptide derivatives in which an alkyl group has been introduced into an amino group which exhibit an extremely high degree of sweetness. However, these compounds still lack the desired stability properties.